Battalion Wars 2 tips?

Yo, just bought this awesome game that i ran into and that caught my attention. Its a very nice tactical game in 3rd person view and really works up your brain. Anyways, i would like to know if you guys could share some tips related to Wi-Fi experience in Skirmish and Assault. I honestly need some practice and my record can show. I've one once or twice but have round 4~5 loses. I dont understand "how to win". My tactic is very simple.

Somehow, i just dont have enough time as the enemy charges me right away so then i just have my button on the "All" command and start calling attacks on one specific target. Does it work? apparently not as my units start dying as fast as if you set them on fire.

Any tips you could share? I must say it is beyond my experience with the campaign modes (by that I mean that the players are really really good if not then i lack experience )